Strawberry plant named ‘UCD Valiant’

ABSTRACT

‘UCD Valiant’ is a day-neutral cultivar of a strawberry plant that provides high yields and produces large, firm fruit. The variety has performed particularly well in low-input and organic production systems.

Genus and species: The strawberry cultivar of this invention isbotanically identified as Fragaria X ananassa Duchesne.

Variety denomination: The variety denomination is ‘UCD Valiant’.

BACKGROUND OF THE INVENTION

This invention relates to a new and distinct day-neutral strawberrycultivar designated as ‘UCD Valiant’, which originated from a crossperformed in the winter of 2011 between ‘Merced’ (U.S. Plant Pat. No.25,436) and proprietary germplasm parent 07C092P003 (unpatented). Seedsof the cross were harvested from greenhouse-grown plants in the springof 2011 and germinated in June 2011. Seedlings were transplanted to agreenhouse in July 2011 and transplanted to the field in October 2011.‘UCD Valiant’ was selected and clones were first harvested in 2012. ‘UCDValiant’ has been asexually propagated since 2012.

The plant of this selection was originally designated ‘11C103P001’ (alsorepresented as 11.103-1) and later called ‘16DN011’ or ‘UC11’ forevaluation in field trials. ‘UCD Valiant’ was also called ‘15 MBA-3’ forcertain testing trials.

BRIEF SUMMARY OF THE INVENTION

‘UCD Valiant’ is a day-neutral (ever-bearing) strawberry cultivarselected for increased marketable fruit yield, earliness, and extendedshelf-life. ‘UCD Valiant’ provides higher yields in low-input andorganic production systems, and produces fruit earlier than other highyielding day-neutral cultivars in the southerly locations in the coastalCalifornia day-neutral environments. ‘UCD Valiant’ exhibits earlierflowering and increased numbers of stolons compared to parent07C092P003, and is day neutral compared to short day parent Merced.

‘UCD Valiant’ produces fruit earlier than ‘Cabrillo’ (U.S. Plant Pat.No. 27,830) and produces more marketable fruit per hectare compared to‘Monterey’ (U.S. Plant Pat. No. 19,767) and ‘Cabrillo’. ‘UCD Valiant’exhibits an early season yield spike in the southernmost day-neutralenvironments tested compared to the yields for ‘UCD Moxie’ (U.S. Plantpatent application Ser. No. 16/501,376), although the cumulativemarketable yields of ‘UCD Valiant’ are not significantly different fromthose of ‘UCD Royal Royce’ (U.S. Plant patent application Ser. No.16/501,374) or ‘UCD Moxie’. ‘UCD Valiant’ is a day-neutral cultivar,whereas parent variety ‘Merced’ is a short-day cultivar.

‘UCD Valiant’ was genotyped with a 35,000-SNP array (Hardigan et. al.,Plant Genome 11:180049, 2018). The variety has a unique DNA profilecompared to ‘Cabrillo’, ‘Monterey’, ‘UCD Royal Royce’, and ‘UCD Moxie’.The pairwise genetic distances between ‘UCD Valiant’ and ‘UCD Moxie’,‘UCD Royal Royce’, ‘Cabrillo’, and ‘Monterey’ are estimated to be 0.223,0.270, 0.307, and 0.266, respectively based on the 35,000-SNP genotypeanalysis. ‘UCD Valiant’ also has a unique DNA profile compared to eachof its parents, ‘Merced’ and proprietary germplasm variety 07C092P003.

‘UCD Valiant’ is maintained by annual asexual propagation by stolons inWinters, Calif.

BRIEF DESCRIPTION OF THE DRAWINGS

The colors in the photograph are depicted as nearly true as isreasonably possible to obtain in color reproductions of this type.

FIG. 1 shows fruit of ‘UCD Valiant’ in cross-section.

FIG. 2 illustrates color of the fruit.

FIG. 3 depicts general flowering and fruiting characteristics of ‘UCDValiant’.

FIG. 4 shows representative fruit trusses of the plant.

FIG. 5 shows representative flowers of the plant.

FIG. 6 shows representative leaves of the plant.

FIG. 7 depicts plant habit.

DETAILED DESCRIPTION OF THE INVENTION Fruit Production

‘UCD Valiant’ and comparison cultivars were asexually propagated inhigh-elevation nurseries in Dorris and Mcdoel, Calif. for field testingin 2015-2016, 2016-2017, and 2017-2018. Clones were harvested accordingto commercial planting schedules, which were calibrated by the number ofchill hours required for optimum production in Santa Maria andPrunedale, Calif.

Cultivar testing in small-plot yield trials was performed as follows.Test day-neutral cultivars and comparison cultivars were field tested inOso Flaco (Santa Maria, Calif.) and Prunedale, Calif. in 2015-2016.Fruit was harvested once or twice per week over the spring and summergrowing season: March 16 to Aug. 18, 2016 in Santa Maria (31 harvests)and April 2 to Aug. 27, 2016 in Prunedale (30 harvests). ‘UCD Valiant’was selected on the basis of fruit appearance, size, shelf-life, andcumulative marketable fruit yield for a second year (2016-17) ofreplicated testing in Santa Maria and Prunedale (Tables 1-2). Fruit washarvested once or twice per week over the growing season: March 13 toAug. 21, 2017 in Santa Maria (25 harvests) and April 3 to Sep. 1, 2017in Prunedale (44 harvests in Prunedale). To highlight differences amongcultivars, the yield data were displayed in three ways: (a) per plantyields for individual harvests for each location x year combination for‘UCD Valiant’, ‘Monterey’, ‘San Andreas’, and ‘Cabrillo’; (b) per plantcumulative marketable yields for ‘UCD Valiant’, ‘Monterey’, ‘SanAndreas’, and ‘Cabrillo’; and (c) per plant cumulative marketable yieldstested in both years and locations. Entry ranks were highly consistentand the best and worst performing cultivars were virtually identicalover locations and years.

Table 1 shows marketable yield (g/plant) for ‘UCD Valiant’ compared tothat for ‘Monterey’, ‘San Andreas’ (U.S. Plant Pat. No. 19,975), and‘Cabrillo’ tested in small-plot yield trials in Santa Maria, Calif. andPrunedale, Calif. in 2015-16 and 2016-17.

Table 2 shows the range in increase in yield compared to ‘Monterey’,‘San Andreas’, and ‘Cabrillo’ for the small-plot yield trials.

TABLE 1 Least-square means for cumulative marketable yield tested insmall-plot yield trials in Santa Maria, CA and Prunedale, CA in2015-2016 and 2016-2017 Yield across Locations and Santa Maria PrunedaleYears Cultivar 2015-16 2016-17 2015-16 2016_17 (g/plant) UCD Valiant1,984 2,380 1,460 2,482 2,078 Cabrillo 1,617 2,073 1,362 2,299 1,838Monterey 1,115 1,324 1,077 1,722 1,310 San Andreas 1,229 1,096 1,0481,569 1,236

TABLE 2 Least-square means for cumulative marketable yield (g/plant)across years and locations in the small-plot yield trials. The rangesfor yield increases over comparison cultivars were estimated from leastsquare means for individual environ- ments (see, Table 1). (PercentMarketable Fruit = (Cumulative Marketable Fruit Yield)/(Cumulative TotalFruit Yield) Yield Yield Yield Increase Increase Increase Percent RangeRange Range Yield Marketable Over San Over Over Cultivar (g/plant) FruitAndreas Monterey Cabrillo UCD Valiant 2,078 84-86 39-117% 35-80% 7-22%Cabrillo 1,838 86-87 Monterey 1,310 79-82 San Andreas 1,236 76-84

The cumulative marketable fruit yields of ‘UCD Valiant’ weresignificantly greater than ‘Monterey’ (p<0.0001), ‘San Andreas’(p<0.0001) and ‘Cabrillo’ (p<0.055) across years and locations (Table1). The per plant yields of ‘UCD Valiant’ were 7 to 117% greater than‘Cabrillo’, ‘Monterey’, and ‘San Andreas’ (Table 2). The mean fruit sizefor ‘UCD Valiant’ (35.3 g/fruit) was significantly different from‘Cabrillo’ (30.0 g/fruit; p<0.0001), Monterey (28.4 g/fruit p<0.0001),and ‘San Andreas’ (26.7 g/fruit; p<0.0001).

The marketable fruit percentages for ‘UCD Valiant’ and ‘Cabrillo’ werecomparable (84-87%) and superior to ‘Monterey’ and ‘San Andreas’ (76 to84%) (Table 2).

‘UCD Valiant’ was selected, with other test varieties, for advancedtesting in large-plot yield trials (150 plants/plot) with fivecommercial growers in 2017-18. The selection criteria were: highcumulative marketable yields, high marketable fruit percentages,resistance to bruising and deterioration with harvest, handling, andstorage, fruit appearance, and reduced runner production in coastalproduction environments. The production systems for large-plot yieldtrials were diverse and included: low-input organic (Santa Maria,Calif.), low-input fumigated (Salinas, Calif.), and high-input fumigated(Oso Flaco, Calif., Prunedale, Calif. and Moss Landing, Calif.). Fruitwas harvested from February 2 to October 5 in Oso Flaco (52 harvests),April 3 to October 4 in Santa Maria (53 harvests), April 12 to October 6in Prunedale (48 harvests), May 7 to October 8 in Moss Landing (45harvests), and March 9 to October 12 in Salinas (36 harvests). Theresidual for statistical analyses was the entry x location interactionmean square.

TABLE 3 Least square means for cumulative marketable fruit yield(cartons/acre) for ‘UCD Valiant’, ‘Monterey’, and ‘Cabrillo’ grown inunreplicated large-plot (150 plant) yield trials in five locations in2017-18, where a carton = eight clamshells and eight clamshells/carton xone pound/clamshell = eight pounds/carton. Santa Oso Mossing AcrossCultivar Salinas Maria Flaco Prunedale Landing Locations UCD Valiant11,241 11,490 16,155 16,135 8,878 12,780 Cabrillo 5,201 6,892 17,56914,057 9,465 10,637 Monterey NA 7,891 14,731 11,940 10,257 10,274

TABLE 4 Least square means for fruit weight (g/fruit) for ‘UCD Valiant’,‘Monterey’, and ‘Cabrillo’ grown in unreplicated large-plot (150 plant)yield trials in in five locations in 2017-18, where fruit weight =(weight of fruit per clamshell)/(number of fruit per clamshell). SantaOso Prune- Mossing Across Cultivar Salinas Maria Flaco dale LandingLocations UCD Valiant 31.2 24.3 32.1 31.2 38.7 31.5 Cabrillo 26.1 21.928.0 27.5 34.0 27.5 Monterey NA 21.6 29.4 27.9 33.8 27.8

TABLE 5 Statistical significance (Pr > F) of differences between leastsquare means for cumulative fruit yield (cartons/acres) and fruit weight(g/fruit) for ‘UCD Valiant’, ‘Monterey’, and ‘Cabrillo’tested inunreplicated large-plot (150 plant) yield trials in five locations in2017-18. Yield Fruit Weight (g/fruit) Difference Difference Comparison(carton/acre) Pr > F (g/fruit) Pr > F UCD Valiant-Monterey 2,506 0.02033.68 <0.0001 UCD Valiant-Cabrillo 2.143 0.0307 4.01 <0.0001

The mean cumulative marketable yield of ‘UCD Valiant’ was 12,780cartons/acre=102,240 pounds/acre across production systems and locations(Table 3). The cumulative marketable fruit yields of ‘UCD Valiant’ weresignificantly greater than ‘Monterey’ (p=0.02) and ‘Cabrillo’ (p=0.03)across production systems and environments. ‘UCD Valiant’ produced 2,506cartons/acre more than ‘Monterey’ (p=0.008) and 2,143 cartons/acre morethan ‘Cabrillo’ (Tables 3 & 5). ‘UCD Valiant’ provided high yields inboth of the low-input production systems tested (Santa Maria andSalinas). ‘UCD Valiant’ fruit weights were significantly larger than‘Monterey’ (p<0.0001) and ‘Cabrillo’ (p<0.0001) (Tables 4 & 5).

To assess the quality of freshly harvested fruit, firmness (gramsforce), total soluble solids (SS) concentration, and titratable acid(TA) concentrations were measured from samples of fruit harvested onthree dates from each location in 2017-18 (Tables 6-7). Harvest dateswere one month apart with one replication per harvest date, 10sub-samples per replication for firmness, and three subsamples perreplication for SS and TA. Firmness was quantified with a hand-heldpenetrometer measuring the grams of force needed to puncture the fruit.SS and TA concentrations were quantified with benchtop instruments. TheSS to TA ratio provides a relative measure of sweetness. To assessshelf-life, fruit weight (g/clamshell), SS, brightness (ordinal scalewith 1=excellent to 5=unmarketable), liquid leakage (g/clamshell), andmold incidence (%) were quantified from samples of fruit harvested ontwo dates from each location with fruit stored under standard 4° C.conditions for 0, 7, 14, and 21 days (Table 8). Harvest dates were onemonth apart with one replication per harvest date.

TABLE 6 Least-square means (LSMs) for firmness, soluble solids concen-tration (SS), and titratable acid concentration (TA) for ‘UCD Valiant’,‘Monterey’, and ‘Cabrillo’ grown in five locations in 2017-18. LSMs wereestimated from three harvest dates per location, one biologicalreplication per harvest date, 10 sub-samples per harvest date forfirmness, and three sub-samples per harvest date for SS and TA. TitrableFirmness SS Acids Cultivar (g force) (%) (g/100 ml) SS/TA UCD Valiant377.44 7.62 0.83 9.19 Cabrillo 359.61 8.05 0.77 10.50 Monterey 294.558.71 0.77 11.48

TABLE 7 Statistical significance (Pr > F) of differences between leastsquare means for SS, TA, and SS/TA for ‘UCD Valiant’, ‘Monterey’, and‘Cabrillo’ tested in unreplicated large-plot yield trials in fivelocations in 2017-18. Soluble Solids Titratable Acids ConcentrationConcentration (SS) (TA) Least Least SS/TA Square Square Least Mean MeanSquare Com- Difference Difference Mean parison (%) Pr > F (g/100 ml)Pr > F Difference Pr > F UCD −1.09 0.0041 0.07 0.0147 −2.29 <0.0001Valiant- Monterey UCD −0.43 0.2624 0.06 0.0354 −1.31 0.0028 Valiant-Cabrillo

TABLE 8 Least-square means (LSMs) for fruit weight (g/clamshell),soluble solids concentration (SS), fruit brightness, liquid leakage, andmold formation for ‘UCD Valiant’, ‘Monterey’, and ‘Cabrillo’ grown infour locations in 2017-18 and stored for zero to 21 days postharvest.LSMs were estimated from two harvest dates per location Days Post-Soluble Liquid Harvest Weight Solids Bright- Leakage Mold CultivarStorage (g/clamshell) (%) ness (g) (%) UCD Valiant 0 576.4 7.1 1.4 0.00.0 Cabrillo 0 555.4 7.5 1.3 0.0 0.0 Monterey 0 572.0 9.2 1.2 0.0 0.0UCD Valiant 7 561.1 6.7 2.6 0.0 0.0 Cabrillo 7 538.7 7.4 2.0 0.2 0.0Monterey 7 556.3 9.1 1.8 0.0 0.0 UCD Valiant 14 546.4 7.0 3.8 0.8 1.3Cabrillo 14 522.9 7.3 3.3 0.8 1.2 Monterey 14 542.3 9.5 3.0 0.0 0.5 UCDValiant 21 527.5 6.8 4.8 24.2 31.7 Cabrillo 21 504.4 7.3 4.3 35.8 36.7Monterey 21 526.4 8.7 3.8 0.2 11.8

‘UCD Valiant’ produced fruit meeting or exceeding industry standards formass-production cultivars (Tables 6-8). The fruit was firm, withstoodthe rigors of harvest, packing, and storage, and maintained acceptablefruit quality and appearance for over two weeks of storage. ‘UCDValiant’ produced significantly firmer fruit than ‘Monterey’ (p<0.0001),but not significantly different from ‘Cabrillo’ (p=0.11). ‘UCD Valiant’additionally had significantly lower SS concentration than ‘Monterey’(p<0.004), but was not significantly different from that of ‘Cabrillo’(p=0.26). The SS/TA ration for ‘UCD Valiant’ was significantly lowerthan ‘Monterey’ (p<0.0001) and ‘Cabrillo’ (p=0.0028).

‘UCD Valiant’ maintained adequate marketability and visual appeal over14 days of post-harvest storage, the industry standard (Table 8), as did‘Cabrillo’ and ‘Monterey’. The marketability of fruit stored for 21 dayspost-harvest was inadequate for all three cultivars. Fruit weight andbrightness significantly decreased as post-harvest storage timeincreased (Table 8). The fruit weight decreases were not significantlydifferent among cultivars. Cultivar x post-harvest storage timeinteractions were only statistically significant for liquid leakage andmold formation, with ‘Cabrillo’ deteriorating more than ‘UCD Valiant’and ‘Monterey’ (Table 8).

Disease Resistance Evaluation

‘UCD Valiant’ and additional cultivars were screened for resistance toFusarium wilt, Verticillium wilt, Macrophomina, and Phytophthora crownrot in Davis, Calif. field experiments between 2015 and 2018. Theseincluded 2015-16 and 2016-17 Fusarium wilt screening experiments with480 to 960 entries, a 2015-16 Macrophomina experiment with 960 entries,2016-17 and 2017-18 Verticillium wilt experiments with 480 to 960entries, and a 2017-18 Phytophthora crown rot experiment with 480entries. Entries were arranged in randomized complete blocks experimentdesigns with four single-plant replications per entry. The 2015-16experiments were planted in virgin soil in Davis, Calif. The 2016-17 and2017-18 experiments were planted in fumigated soils in Davis, Calif. Foreach experiment, plants were artificially inoculated with the respectivepathogen and phenotyped for disease symptoms on an ordinal scale, where1=highly resistant (symptomless), 2=resistant, 3=intermediate,4=susceptible, and 5=highly susceptible (dead). Within each experiment,plants were phenotyped at six different time points to study changes inthe phenotypic distributions and quantify the progression of diseasesymptoms over time.

‘UCD Valiant’ was susceptible to Fusarium wilt (4.5 on scale),moderately susceptible to Verticillium wilt (3.3 on scale), moderatelysusceptible to Phytophthora crown rot (3.0 on scale), and susceptible toMacrophomina (5.0 on scale).

BOTANICAL DESCRIPTION

The following botanical descriptors are characteristic of ‘UCD Valiant’.The descriptors were collected from two different sites in May 2017 inSanta Maria, Calif. Colors are designated with reference to The RoyalHorticultural Society (R.H.S.) Colour Chart, Sixth Edition, 2015. Thecharacteristics of ‘UCD Valiant’ may vary in detail, depending uponenvironmental factors and culture conditions.

-   Growth habitat: Semi-upright Plant height average of 35 cm. Plant    spread average of 40 cm.-   Density of foliage: Medium.-   Vigor: Strong.-   Position of inflorescence in relation to foliage: Above.-   Number of stolons: Average of 8.-   Stolon, anthocyanin coloration: 60B.-   Stolon, density of pubescence: Sparse.-   Leaf size: Medium.-   Leaf color: Adaxial 143A, Abaxial 138B.-   Leaf blistering: Medium.-   Leaf glossiness: Medium glossy.-   Leaf variegation: Absent.-   Terminal leaflet, length in relation to width: Average of 80 mm long    and 76 mm wide.-   Terminal leaflet, shape of base: Obtuse.-   Terminal leaflet, margin: Serrate to crenate.-   Terminal leaflet, shape in cross section: Concave.-   Petiole, length: Average of 20 cm.-   Petiole, attitude of hairs: Upwards.-   Stipule, anthocyanin coloration: Core color 144D, Margin color 144A    (absent or weak).-   Inflorescence, number of flowers: Many.-   Pedicel, attitude of hairs: Upwards.-   Pedicel, anthocyanin coloration: 60B.-   Flower diameter: Average of 25 mm.-   Flower, arrangement of petals: Free.-   Flower, size of calyx: Calyx diameter average of 24 mm.-   Color of calyx: 137B.-   Flower stamen: Present.-   Number of stamens per flower: Average of 26.-   Number of sepals per flower: Average of 12.-   Petal, length in relation to width: Equal, Average of 10 mm long and    9 mm wide.-   Petal, color of upper side: NN155B.-   Petal, color of lower side: NN155B.-   Number of petals per flower: Average of 6.-   Fruit, length in relation to width: Average of 51 mm long and 41 mm    wide.-   Fruit size: Average of 35 grams through the season for both primary    and secondary fruit.-   Fruit shape: Conical.-   Fruit, difference in shape of terminal and other fruits: Slight.-   Fruit color: 45A.-   Fruit, evenness of color: Even or very slightly uneven.-   Fruit glossiness: Strong.-   Fruit, evenness of surface: Even or very slightly uneven.-   Fruit, width of band without achenes: Absent or very narrow.-   Fruit, positions of achenes: Below surface.-   Achene color: 4A.-   Fruit, position of calyx attachment: Inserted.-   Fruit, attitude of sepals: Upwards.-   Fruit, diameter of calyx in relation to fruit diameter: Slightly    smaller.-   Fruit, adherence of calyx: Weak.-   Fruit firmness: Firm.-   Fruit, color of flesh (excluding core): 33A.-   Fruit, color of core: 41C.-   Fruit cavity: Average of 4.4 mm.-   Time of beginning of flowering: Early, starts in January to October.-   Time of beginning of fruit ripening: Early, starts in February to    November.-   Type of bearing: Day neutral.

PLANT AND FOLIAGE COMPARISONS

Fruiting plants of ‘UCD Valiant’ are similar in height to ‘Monterey’,but slightly taller than ‘Cabrillo’ and ‘San Andreas’. The spread isslightly more compact than ‘Monterey’ and ‘Cabrillo’ and more similar to‘San Andreas’. Leaves (including petioles) for ‘UCD Valiant’ are longerthan for all three comparative cultivars. Color for the upper and lowerlevels of the leaves of ‘UCD Valiant’ are lighter green than ‘Monterey’and ‘Cabrillo’ and more similar to ‘San Andreas’. Serrations atmidseason are more pointed than ‘Monterey’ and more similar in shape andnumber to ‘Cabrillo’ and ‘San Andreas’. The stipule length of ‘UCD’Valiant is shorter than all three comparative cultivars. Stolonproduction of ‘UCD Valiant’ is greater than ‘San Andreas’, but less thanfor ‘Cabrillo’ and ‘Monterey’.

FLOWERING AND FRUITING COMPARISONS

‘UCD Valiant’ is similar to other California day-neutral cultivars (e.g.‘Cabrillo’, ‘Monterey’ and ‘San Andreas’) in that it will flowerindependently of day length, given appropriate temperature andhorticultural conditions. General tendency is for flowering to initiateearlier than the cultivars ‘Monterey’ and ‘Cabrillo’ and more similar to‘San Andreas’. The primary flowers for ‘UCD Valiant’ are similar in sizeto the comparative cultivars with a calyx that is slightly largerrelative to the corolla on the primary fruit. The sepals for ‘UCDValiant’ are similar in length and width compared to ‘San Andreas’, butshorter and narrower than ‘Monterey’ and ‘Cabrillo’. The calyx of ‘UCDValiant’ is variable (reflex to flat) more similar to ‘Monterey’ and‘San Andreas’, and less reflexive than ‘Cabrillo’. The fruit shape of‘UCD Valiant’ can vary through the season, but is generally a conicfruit as compared to the long conic fruit of ‘San Andreas’, the shortand rounded conic fruit of ‘Cabrillo’ and the short and slightlyflattened conic fruit of ‘Monterey’. External fruit color of ‘UCDValiant’ is similar to ‘Monterey’, but slightly darker than ‘Cabrillo’.The internal fruit color of ‘UCD Valiant’ is similar to ‘Cabrillo’, butlighter than ‘Monterey’.

Achenes of ‘UCD Valiant’ are slightly indented in the fruit,comparatively similar to the fruit of ‘Cabrillo’ and ‘San Andreas’,whereas the achenes of ‘Monterey’ are more flat to the surface position.

What is claimed is:
 1. A new and distinct cultivar of strawberry planthaving the characteristics substantially as described and illustratedherein.